Crowned cupped resilient plug for cylindrical passages



Dec. 11, 1951 M. L. LOCKHART 2,577,780

CROWNED CUPPED ,RESILIENT PLUG FOR CYLINDRICAL PASSAGES Filed May 9,1950 'JJJIMJIIJMIIIIIJMFJ Patented Dec. 11, 1951 UNITED STATES rarestorricr.

cRoWNnncUPP n RESILIENT PLUG- FOR CYLINDRICAL PASSAGES Marshall L;Lockhart, RutherfordLlN. J., assignor, by direct and mesne assignments,to The Com pule Corporation, Rutherford,

.. ration of New Jersey N; J.,- a corpo- Application May '9, 1950,Serial No. 160,987

. tures which may serve as a; piston plug'therein,

and is adapted especially'to use ihsme'di'cinal storage vials, ampules,hypodermic injection syringes; etc.

A general object of the present invention is to provide such plugs fromresilient -m'aterial, generally of a crowned cupped shape, which areeasily and economically'rnass produced and which permit use thereofefficiently as-stoppersfor tubular structures, as piston plugs forexpelling .fiuids. from ampule tubes and syringe barrels,

or as partitioning'means in tubes readily provided, if desired, withpiercedslits effectively to 'serve as efficient one-way valves, i. e.,permitting passage of fluids under pressure from within the cuppedchambers in the plugswhile blocking reverse fiow; the crowned closureendsof the plugs being of such shape and soproportioned as to avoid anytendency to bulge laterally with in- ,ent zone so proportioned anddisposed as to prevent undue lateral bulging. thereof with in-foldingunder pressure applied either mechanically or by means of fluid so thatfolds thereof will not extend laterally an appreciable distance beyondthe outermargins of the plug to overlap edges ofthe tubular structurewhen employed as a stopper in an end thereof.

Another object of thepres ent. invention is to providelsuch a crownedcupped resilient plugv in which the domed closure end-is readilypierceable to. provide fluid passage slits which permit escape of fluidwhen pressurethereof is applied. internally; of the hollow plug andwhichmaybe effectively closed to passage of fluid when pressurethereofislappliedto the outside offt h'e domed end with resultantinefolding' oflthelatter sothat .tn mg; may serve as a one-wayfvaive;the. stifieneenp of the domed closure end alsoflbeing re di y i abl i' het;i permi passagetherethrough of a withdrawing needle,

2 such" as that of a hypodermic syringe, and in'such case allowing useof the inherent action of the domed end with periodic applicationthereto and relief therefrom of pressure effectively to provideaspirating action.

A further object of the present invention is to provide structuralembodiments of the plug of the present invention which may be readilymade and allow eflicient use and operation thereof for a variety ofpurposes, as will be more fully apparent from the following description,

Other objects of the invention will in part be obvious and will in partappear'hereina'fter.

The invention accordingly comprises an article of manufacture possessingthe featuresproperties; and the relation of elements which will beexemplified in the article hereinafter described and the scope of theinvention will be indicated in the claims;

For a fuller understanding of the nature'a-nd objects of the invention,reference should be had to the following detailed description taken inconnection with the accompanying drawingyin which:

- Fig. 1 is an enlarged side view of an embodiment of thecrowned cuppedresilient plug of the present invention;

Fig. 2 is an end view shown in Fig; 1 as-observed from the domed closureend thereof;

Fig. 3 is-a longitudinal sectional view, taken substantially on line 3-3of Fig. 2; r

Fig. 4 is a sectional View, with parts broken away, of a tube and theplug shown in Figs. 1, 2 and 3 with the latter positioned in an end ofthe former to serve as a stopper while permitting its use, if desired,.as a piston plug, -and-with-=the domed closure end relaxed;

Fig.- 5 is a sectional view similar to Fig:-4 but showingthe in-foldingof the domed closure end with application of pressure-theretoexternally, a dot-dash lineposition of the so in-folded' plug beingindicated to illustrate its usev as a: piston plug;

.Fig..6 is an axial section to a smaller scale of an ampule comprising atube closed at one end and plugged at the other by the plug illustratedinFigs. l to 5 inclusive, showing afragment of a piston. post or thrustmember associated needle of a syringe structure;

Fig. '7 is a view Similarto Fig. 6 showing infolding of the domedcl'osureend of the plug when pressure is applied thereto by means-ofthe. piston post of the syringe after the-needle has piercedtherethrough; I v f 8.is -a view similar to Fig; 6 showing, the

relative position of the parts upon relief of the pressure applied inconnection with the Fig. '7 illustration so as to provide aspiratingaction;

Fig. 9 is an axial section of a tubular structure or barrel in which theplug of the present invention is located to serve as a one-way valvepartition structure, with another piston plug being employed to createhydraulic pressure in contained liquid to force the latter from theinterior chamber of the crowned cupped plug through pierced slits in itsdomed closure end; and

Fig. is a side elevational view of a modified form of the crowned cuppedresilient plug of the present invention shown in Figs. 1 to 9 inclusivewherein the base sleeve section has a truly cylindrical external surfacefree from circumferential grooving; that view including in dotted linesa portion of a tube having a waist constriction with the plug serving atthe constriction as a partitioning means.

Cupped rubber plugs have been commonly used in ampules and syringebarrel structures to serve as stoppers therefor and to act when desiredas piston plugs for discharge of liquid contents when mounted insuitable syringe structures, as will be noted from my prior Patent2,490,447 of December 6, 1949. However, when such plugs are closed offat the end by a transversely-extending wall, they are of limited use,since aspiration of a desired degree is not practically attainabletherewith. Highly crowned plugs which permit a desired degree ofaspiration have been used, but when the crown of such a plug projectsfrom the end of a tubular barrel structure or ampule, external pressurethereagainst causes it to flop over or bulge laterally to beyond theedge of the tube, thus undesirably interfering with certain uses of theplug, such as for a piston plug. These and other difficulties of priorart attempts are efficiently eliminated by the crowned cupped resillient plug of the present invention, which additionally permits effectiveuse thereof as a blocking or one-way valve partition at a point betweenthe ends of tubular structures.

As will be seen from the drawing, in which like numerals identifysimilar parts throughout, an embodiment of the present inventionillustrated in Figs. 1 to 8 inclusive may comprise a body ll ofresilient material, such as synthetic or natural rubber or gum and thelike, having a substantiallycylindrical base sleeve section l2 and adomed protruding closure end is circumferentially joined to the formerat its outer end l4. As best seen in Fig. 3, the walls of the basesleeve section 12 are relatively thick to be appreciably resistive todistortion while permitting limited diametrical constriction to allow afluid-type fit into a tubular structure, such as a circular hole, tubeor cylindrical barrel. The domed protruding closure end I3 is providedwith a stiffened transversely-extending central section Hi to definebetween its margins and the outer end I4 of the base sleeve section I2 asubstantially conical zone portion H, which, as will be seen from Fig.3, is formed of relatively thin stock so as to be of greater flexibilitythan both the central section and the base sleeve section. Preferably,the central section 16 is formed by a circular protrudin rib l8 arrangedabout a circular, relatively thin-walled, transverse tip membrane l9, sothat the latter is easily pierceable by a needle while serving as a partof the relatively rigid central section i5. However, it will be understood that all of the central section [B may if desired, be in theform of a relatively pad of substantially uniform thickness,particularly if the use of the plug is such as not to require centralpiercing thereof by a needle or should certain resistance to suchpiercing be unobjectionable.

As indicated in Fig. 3, the outer surface of the zone I! preferably hasits generatrix, as represented by the dotted line 20, disposedsubstantially at an angle X of about 45 to the plug axis, as representedby a dot-dash line 2!. It has been found, in accordance with the presentinvention, that 45 is about the minimum limit of that angle in order toassure elimination of any tendency for the domed protruding end it toflop over under external pressure or to bulge laterally to aninterfering degree. It is to be under- 7 stood that the domed protrudingend I 3 may,

within the scope of the present invention, be flatter than that shown byway of example in the drawin so that angle X approaches to within a fewdegrees of with the plug axis 2!. However, the flatter the domedprotruding end i3 is, the lesser is the aspirating action which isattainable by the plug. It will thus be seen that in the preferredembodiments the zone I! is in the shape of the surface of a frustum of aright cone, but other shapes thereof which closely approach the samewhile possibly providing slightly curved Walls'in that zone, eitherconvex or concave to a small degree, are contemplated within the scopeof the present invention and the terminology used herein.

In the preferred embodiments shown in the drawing, the bore 22 of thebase sleeve section (2 is preferably constricted or throated at 23 toassure an appreciable thickness of the walls 15, at least at that point,for attainment of the desired relative resistivity to distortion orrigidity. The

bore 22 is flared out as it, approaches the outer end M of base sleevel2 so as to permit circumferential connection thereto of the base end ofthe frusto-conical section [1 at an appreciable diametrical distancefrom the axis 2|, thereby assuring a fair width of the flexible zone topermit good flexing action. It will thus be seen from Fig. 3 that thechamber 24 provided within the crowned cupped resilient plug I! issubstantially bulbous.

I In the structure shown in Figs. 4 and 5, tube 25 may be an end portionof a syringe barrel or an ampule of the type shown in my prior patentidentified above, with one end closed by the plug H. of the resentinvention. Assuming that the tube 25 is the cartridge sleeve of an amule intended for use in a Cock type of syringe, as illustrated in U. S.Patent 1,661,818 of March 6, 1928, so as ts serve as the'bar'relthereof, the crowned cupped plug H of the present invention serves asthe closing piston plug in one end thereof. It is well understood in theart that in order to discharge liquid contents or such a. barrel throughthe needle of such a syringe structure, such piston plug is forced toslide down therein by depression of a suitable plunger. In Fig. 5,responsive distortion of the present plug to such plunger action isillustrated. It will there be seen that with application of pressureexternally to the protruding tip of the plug. II, as diagrammaticallyindicated by the arrow 26, the domed protruding closure end I3 isdistorted inwardly with flexure of the zone l1. During such flexure ofzone ll, there is no appreciable lateral bulging of the plug in thevicinity of the end M of base sleeve I2, or any .of such degree as tocause the formation, of. a $01 1. which would overmam-mo.

:lap -the edge' 21 of the; tube 23 torsuchean: extent as to" intei'f erewith piston -sliding action: thereof. "Such. piston action. is"illustrated ".5 -xb 1z 'a dot-dashoutline at*28, which represents'thelocation of the plug: when: pushed" inwardly the dis.- tancebetween the130111135 29 .andf30. Therm;- folding of the tip I3 hasbeenaeimggerated. in

Fig; 5 in order toavoid anypossible" confusion the: showing of thatfigure.

In-Fig; 6; the tube 25 is illustrated aszaniampule adapted to-serve asthe-barrel: ofxa syringe structure of the type illustrated; in my aboveidentified patent. Ampule tube 25 of Fig; 6 contains a body 3 I ofmedicinal solution intended for; hypodermic injection; with i the end:of thei'tube suitably-=closed off by plug II. of; the. present.tinvention. A portion of pistona-post:ortthrust'memb'er 32 of" thesyringe: structureuand thezassociated inner end 33 of. a' double-ended:injection needle .are' shown with the 'latter'being thrust intcs'themembrane: I9. 'After the syringe needle has been properly inserted intoa patients flesh. the domed end of the plug H will-be depressedor'insfolded,

as shown in' Fig. 7,."by pushing"theampulei25 toward the: post or.thrust 'membert32. As a .2

result, the space withinu the; ampule' will: be: reduced so asmomentarily totdischargelthrough the" needle a; small quantity of fluidcontents. Then,.fupon relief 'ofpressurei against ampule 25,

asshown in Fig.1 8 the. resiliency of 'thexplug II will cause itsdomedend to protrude againwith suction being createdr onv needle .33,'to'..:provide.1a

Idesired. aspiratinge action- The employment :of the 'plug of. thepresent invention. as a valved-partition in a tubularstructure .isillustrated in: Fig. '9" wherein a .portionof tube. I25 is shown fittedbetween. its ends with one of the plugs" I I- The latter preferablyprovided. with; a plurality of: pierced slits 34'34 in the .zone' [1,.such: asby: thrusting a. needle therethrough: at a plurality of pointsaboutflthe tip I6. As a result,'when' hydraulic pressure is appliedchamber. 24 by" forcing :arpiston. plug 35' of usual construction. intothe tube. in the direction of the arrow indicated, liquid I3I: will becaused tobulge the idomed end, as shown; with an. attendant? opening ofthe slits 34-34. Consequently, liquid is caused to passthrough thepartitioniplug via the" open. slits 3'4''-34. .Their location in thezonell ispreferred. since it will direct resulting jets of liquid againstthe; inner wallsoflthe tube I25, rather than axially togive a fountainactionwhich may be undesirable. If, however, such fountairr- -action isnot objectionable, membrane l9 within the stiffening rib I8 may also beprovided with a needle-pierced slit I 34 to supplement the action of theslits 34-44. The opening of the slits 34-34 and I34 under hydraulicpressure applied internally of chamber 24 is, of course, caused by thestretching of the relatively thin flexible walls of zone I! and thecentral membrane I9 as the domed end of the plug II is bulged under theapplication of pressure within the chamber, as is well illustrated inFig. 9. Upon relief of hydraulic pressure with cessation'of slidingmotion of piston plug 35, the domed end of the piston plug II will relaxso that the pierced slits 34-34 and I 34 will naturally close bycontraction of the resilient walls of zone I! and membrane I9. Thoseslits will remain effectively closed against any pressure appliedexternally of the domed end since such application of externalpressurewill fold it inwardly, such as-is indicated in Fig. 4, and in suchdistorted disposition, the needle-pierced slits remain-efiectivelyclosed against passage of fluid.

"Iii'Fig: mes 'showni in fulllines at. I l'lzanother embodimentzofthexpl'uguof the: presentinvention 'preferred'when it is desired to'u'sethe' sameas a partitioning: means in a tubular; structure having aconstricted waist; such as that indicated-in dotted lines at I2 5. and31: respectively in Fig.1.10. lThe constricted waist-.31.:of1course,mayzbezso dimensioned as to serve eitherrasaa permanent seat for? such Ia partitioning,plug. or as means intended only: temporarily tor retardsliding action of plug II I upon-application: of pressure thereto.

It willv thus. be seen: that the. objects set forth above,.among thosemade apparent; from the rpreceding description, are. efficientlyattained and, since certain changes may be. made. in the: above article,and different. embodiments: off'the; invention could be made withoutdeparting fromithe scope thereof, it is intendedthat" allmatter'contained in the" above deseription'or' shown. in theaccompanying drawing shall be=*interpreted as illustrative arid. not ina limiting sense.

It is alsotobe understood that the following claims are intended" tocover "all of the generic and specificfeaturesof the invention hereindescribed; and all" statements of 'the'scope of the invention which; asa matter 'of'language, might be said to fall therebetween.

Having described my invention, what I claim as new and desire to secureby Letters Patent is:

1. crowned cupped resilient plug for tubular structures comprising ahollow, substantially cylindrical basesleeve section having relativelythickwalls to'be appreciably resistive to distortion whilepermitting-limited diametrical constriction" to allowfluid-tight fittinginto a tubular structure; a domed, protruding closure endcircumferentially joined to'one end of said sleeve section; and astiffened, transversely-extending. central sectionv onsaid domed closureend defining between its margin and said sleeve section a substantiallyconical'zone portion, said closure end Zone being of greater flexibilitythan said central section and said'sleeve section with the g'enerat'r'ixof'the outer surface of said zone being disposed substantially at anangle to the axis of said plug of between about 45 and a few degreesless than 2. The crowned cupped resilient plug as defined in claim 1characterized by the provision of said zone portion in substantially theshape of the surface of a frustum of a right cone with the thicknessthereof being substantially less than the thickness of the Walls of saidbase sleeve section and said stiffened central section to assurerelatively greater flexibility.

3. The crowned cupped resilient plug as defined in claim 2 characterizedby a disposition of the wall of said zone portion relative to the axisof said plug resulting from arrangement of the generatrix of its outersurface at an angle of about 45- to said axis.

4; The crowned cupped resilient plug as defined in claim 3 characterizedby the provision of normally-closed, pierced slits in said domed closureend permitting said plug to serve as a one-way valve with said slitsopening under fluid pressure applied from within said base sleevesection and closing with in-folding of the domed closure and uponapplication of fluid pressure externally thereto.

5. A crowned cupped resilient plug for tubular structures comprising abody of resilient material including a base sleeve provided with relatively thick walls to assure relative rigidity; a relativelythin-walled, highly flexible, frusto-conical section circumferentiallyjoined at its base to and protruding from one end of said sleeve withthe generatrix of its outer surface arranged at an angle to the axis ofsaid plug of between about 45 and a few degrees less than 90; and astiffer, transversely-extending, axially-located section closing off theouter smaller end of said frusto-conical section.

6; A crowned cupped resilient plug for tubular structures comprising abody of resilient material including a base sleeve provided withrelatively thick walls to assure relative rigidity; a relativelythin-walled, highly flexible, frusto-conical section circumferentiallyjoined at its base to and protruding from one end of said sleeve withthe generatrix of its outer surface arranged at an angle to the axis ofsaid plug of about 45; and a stiffer, transversely-extending, axiallylocated section closing off the outer smaller end of said frusto-conicalsection.

'7. A crowned cupped resilient plug for tubular structures comprising abody of resilient material including a base sleeve provided withrelatively thick walls to assure relative rigidity; a relativelythin-walled, highly flexible, frusto-conical section cireumferentiallyjoined at its base to and protruding from one end of said sleeve withthe generatrix of its outer surface arranged at an angle to the axis ofsaid plug of between about 45 and a few degrees less than 90; saidfrustoconical section having normally-closed pierced slits therein to beopened by fluid pressure applied from within said base sleeve; and astiffer, transversely-extending, axially-located section closing off theouter smaller end of said frustoconical section.

8. A crowned cupped resilient plug for tubular structures comprising abody of resilient material including a base sleeve provided withrelatively thick walls to assure relative rigidity; a relativelythin-walled, highly flexible, frusto-conical section circumferentiallyjoined at its base to and protruding from one end of said sleeve withthe generatrix of its outer surface arranged at an angle to the axis ofsaid plug of about 45"; said vfrusto-conical section havingnormally-closed pierced slits therein to be opened by fluid pressureapplied from within said base sleeve; and a stiffer,transversely-extending, axially-located section closing off the outersmaller end of said frusto-conical section.

9. A crowned cupped resilient plug for tubular structures comprising abody of resilient material including a base sleeve having relativelythick walls to assure relatively high rigidity and with its outersurface being substantially cylindrical to be fitted into a tubularhole; a relatively thin-walled, highly flexible frusto-conical sectioncircumferentially joined at its larger base end to one end of saidsleeve and protruding therefrom with the generatrix of its outer surfacearranged at an angle of about 45 to the axis of said plug; and astiffer, transverselyextending tip portion closing off the outer,smaller end of said frusto-conical section with a protrudingcircumambient external stiffening rib thereon arranged about arelatively thin needle-pierceable area thereof.

10. A crowned cupped resilient plug for tubular structures comprising abody of resilient material including a base sleeve having relativelythick walls to assure relatively high rigidity and with its outersurface being substantially cylindrical to be fitted into a tubularhole, the bore of said sleeve being enlarged at its outer end; arelatively thin-walled, highly flexible frusto-conical sectioncircumferentially joined at its larger base end'to the outer end of saidsleeve :and protruding therefrom with the generatrix of its outersurface arranged at an angle of about 45 to the axis of said plug; and astiffer, transversely-extending tip portion closing off the outersmaller end of said frusto-conical section with a protrudingcircumambient external stiffening rib thereon arranged about arelatively thin needle-pierceable area thereof.

' 11. The crowned cupped resilient plug as defined in claim 10characterized by the shaping of the bore in said'sleeve to provide nearits inner open end a constricted throat with the walls of the boregradually flaring from that constriction to' the wider portion thereofat its outer end so that said frusto-conical section is of maximum widthto provide for free flexing action thereof.

' MARSHALL L. LOCKHART.

No references cited.

